1. Field of the Invention
The present disclosure relates to generally method and apparatus for wake up an electronic device having a sensor. More particularly, the present invention relates to method and apparatus for wake-up an electronic device having a sensor, thereby reducing battery power utilized by the portable devices and facilitate a return of the electronic device to operation from a sleep mode.
2. Description of the Related Art
In order to save power, which is of particular importance to battery powered devices, conventionally a “sleep mode” has been utilized, typically when the electronic device is an idle state for a predetermined amount of time.
Battery usage in portable electronic devices is critical. A few examples of the many types of devices where battery usage is critical include but are not limited to, cell phones, smart phones, tablets, personal digital assistants (PDA's), portable music players, etc. Furthermore, continues to be a need to provide more functionality, while at the same time reducing battery power usage.
Conventional devices, wherein after a period of time of non-usage, may dim the brightness of the display, or the display goes blank to conserve energy.
For example, with regard to computers, a sleep mode is defined as an energy-saving standby condition of the computer, wherein the computer can be reactivated by an external stimulus, such as touching the keyboard. For example, when a notebook computer goes into sleep mode, the display screen and disk drive are normally shut down. Once awakened (e.g. by being sent a specific signal), the computer returns to its former operating state.
Moreover, in the case of portable electronic devices, a sleep mode may be operated in many different types of devices, for example, smartphones, tablets, music players, Personal Digital Assistant (PDAs), just to name a few possibilities.
In fact, many smartphones now default to a sleep mode when not used, unless actively performing certain tasks. When there are no active user interactions such as screen touches, every component, including the central processor, may be powered down unless an application instructs the operating system to keep the device or certain components thereof, fully powered on.
Moreover, a number of background operations may need to be performed while the phone is idle. In one such example, a user may need to automatically update an email folder by checking with a remote server. To prevent the phone from going to sleep during such operations, smartphone manufacturers often make application programming interfaces, or APIs, available to app developers. The developer may insert an APIs into one or more apps to instruct the phone to stay awake long enough to perform necessary operations.
In a typical smartphone, an Application Processor (AP) is asleep when the device is asleep. In order to wake up the device, conventional systems require the user to provide a physical input, for example press a power button or an unlock button.
Using a sleep mode or sleep state saves battery power, particularly when compared with leaving a device in a fully operational mode or state while idle, and advantageously permits the user to avoid having to reset programming codes or wait for an electronic device to reboot. In wireless electronic devices, such as portable mobile terminals, tablets, etc., which often seek out networks and have to provide passwords (or have passwords provided to them) to obtain access upon being rebooted or reset, the use of sleep mode is preferable to a rather cumbersome and slow process or rebooting.
However, to return to an electronic device an operational mode (e.g. wake mode) from a sleep mode requires an action to be undertaken by the user. For example, a power button or an unlock icon must be pressed, which is slow and sometimes awkward, especially when trying to quickly perform an action on the electronic device. Even in the case of the electronic device providing a virtual keypad, an unlock icon must be touched, swiped or spread in order to restore the electronic device to an operational mode, meaning that the user is inconvenienced by being required to contact a button of the device, or slide their finger along a screen.
Some conventional attempts to solve some of the shortcomings include providing a luminance sensor or a camera. However, in such cases the application processor (AP) cannot go into sleep mode and must always be in an operating mode in order to monitor and process sensed data from the sensor or camera. This type of monitoring requires a high amount of power consumption, as it is impossible to control the sensor by the AP directly when the AP is asleep.
Recently, the use of a lower power processor for processing only the sensing data has been configured into the devices. However, the low power processor processes data from the sensor using a polling type, and must be maintained in a wake-up state, using significant amounts of power.
With regard to conventional attempts to address the above-discussed issues, U.S. Pat. Appln. Pub. No. 20100313050 discloses that a sensor processor system selects a power profile to be applied to the application processor system based on the sensed data, and instructs the power management controller to apply the selected power profile to the application processor system. There are two processors used for low power sensing that wakes up the AP when the sensed data meets the condition.
However, a significant drawback to U.S. Pat. Appln. Pub. No. 2010/0313050 is that the sensor processor always operates to monitor ambient environment using a polling type sensor without a sleep mode. The sensor processor applies the power profile to the application processor system (S/W type).
In another conventional attempt to improve the art, in U.S. Pat, Appln. Pub. No. 2009/0259865, the electronic device includes a circuit configured to operate when the main processor is in the sleep mode. The circuit comprises at least one low power processor and a sensor. However, the low power processor in the conventional system always operates without being in sleep mode in order to be able to monitor ambient environment via a polling-type sensor.
Accordingly, there is a need in the art for a system and method that permits additional components to be in sleep mode and yet, provides ambient monitoring of the device, and can permit a switch back to an operating mode from sleep mode quickly without pressing buttons or touching the display screen.